Sub Same Building: Date for 4-wires?
#1
03-23-17, 05:51 PM
Sub Same Building: Date for 4-wires?
Has four wires and an isolated neutral bar plus bonded ground bar always been required for subs off the main panel when sub is in the same building?
(I know the rules on detached structures originally didn't require 4-wire unless there was an additional path to ground so just wondering about same building rules.)
(I know the rules on detached structures originally didn't require 4-wire unless there was an additional path to ground so just wondering about same building rules.)
#2
03-23-17, 06:37 PM
Group Moderator
Has four wires and an isolated neutral bar plus bonded ground bar always been required for subs off the main panel when sub is in the same building?
A ground bar is not required, but there has always been the requirement for a grounding path in the installation. It does not need to be a wire, it can also be steel conduit with approved fittings and installation. (IE: EMT) A ground bar can be added later, if needed.
#3
03-23-17, 06:54 PM
Tolyn Replied:
But in http://www.doityourself.com/forum/el...ug-needed.html Post #34 Taz 420 wrote:
I am doubting the 1923 date but maybe I'm wrong.
Yes, sort of. A ground bar is not required, but there has always been the requirement for a grounding path in the installation.
1. You have not been allowed to combine neutrals and grounds after the SE since 1923
Last edited by ray2047; 03-23-17 at 07:20 PM.
